In the conventional 2D to three-dimensional (3D) stereoscopic image conversion technology, a depth of each pixel of a 2D image is estimated and calculated one by one, i.e., in the prior art, different independent estimation and calculation procedures are performed on different pixels, resulting in high calculation resources (e.g., time and circuit areas) in order to accurately estimate the depth of each pixel, and the entire circuit system becomes relatively complicated and costly. Accordingly, for current image processing applications, complicated circuit systems, using many calculation resources, is rather lacking in flexibility. In addition, the conventional technology fails to accurately estimate depth information of image content corresponding to a 2D image, and the conventional 2D image to 3D stereoscopic image conversion technology also creates serious distortion when the 2D image is converted to a 3D stereoscopic image. These are some of the problems faced in the prior art in this field which the current invention serves to address.